Optimize java.io.UnixFileSystem to avoid ErrnoException churn.#2762
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Optimize java.io.UnixFileSystem to avoid ErrnoException churn.#2762copybara-service[bot] wants to merge 1 commit into
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Replace Libcore.os.access with Libcore.os.canAccess in UnixFileSystem.checkAccess(). Libcore.os.access throws ErrnoException on failure (e.g. when a file does not exist), which must be caught and handled. On iOS, throwing ObjC exceptions has a significant performance cost (stack unwinding, runtime locks) and also litters "Earlier exception" logs in Crashpad/Breakpad crash reports, obscuring real errors. Libcore.os.canAccess performs the same POSIX access check but returns a boolean (false on failure) without throwing any exceptions, completely eliminating the exception churn for File.exists(), File.canRead(), and File.canWrite() checks that return false. PiperOrigin-RevId: 922403915
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Optimize java.io.UnixFileSystem to avoid ErrnoException churn.
Replace Libcore.os.access with Libcore.os.canAccess in UnixFileSystem.checkAccess().
Libcore.os.access throws ErrnoException on failure (e.g. when a file does not exist), which must be caught and handled. On iOS, throwing ObjC exceptions has a significant performance cost (stack unwinding, runtime locks) and also litters "Earlier exception" logs in Crashpad/Breakpad crash reports, obscuring real errors.
Libcore.os.canAccess performs the same POSIX access check but returns a boolean (false on failure) without throwing any exceptions, completely eliminating the exception churn for File.exists(), File.canRead(), and File.canWrite() checks that return false.